In healthy humans and animals, after the intrusion of a foreign substance (the antigen) the body will attempt to attack this antigen by generating specific antibodies which are directed against this antigen. Most individuals are in general tolerant to substances which occur in their own body. Some individuals on the other hand generate antibodies against endogenous substances, tissues, or components. Such antibodies (auto-antibodies) cause great damage to the organs which contain these endogenous substances. The development of the associated auto-immune disease is in general very slow (a matter of years) and this hampers timely clinical diagnosis and treatment to a high degree. Diagnosis can generally only be made after appreciable damage has already been caused to the body. Earlier research has shown that many of these auto-antibodies are syndrome-specific, i.e. the disease seems to be characterized by the occurrence of specific auto-antibodies.
Furthermore, it appears from recent research that these specific auto-antibodies can often be detected in the serum of a patient long before the clinical diagnosis can be made with certainty. The auto-antibodies therefore predict, as it were, which disease is developing.
The timely detection of these auto-antibodies in the patient's serum is the more important because the patient's treatment can then be initiated earlier, thereby delaying, or even preventing, the often serious damage during the later phase of the disease.
Patients with an auto-immune disease possess auto-antibodies directed against one or more protein antigens, such as small protein molecules which occur in the cell nucleus and which are complexed with ribonucleic acid, such as the so-called snRNPs (small nuclear ribonucleo-proteins).